The invention relates to improvements in apparatus for transporting articles between spaced-apart locations, e.g., between the outlet or outlets of one or more article making, storing and/or processing machines and the inlet or inlets of one or more further processing or storing machines. Typical examples of articles which can be transported in the apparatus of the present invention are rod-shaped articles of the tobacco processing industry including plain or filter (smoke generating or smokeless) cigarettes, cigars and cigarillos containing natural, reconstituted or substitute tobacco, as well as filter rod sections of unit length or multiple unit length. More particularly, the invention relates to improvements in apparatus for transporting so-called mass flows of articles, e.g., layers of parallel or substantially parallel rod-shaped articles of the tobacco processing industry. Still more particularly, the invention relates to improvements in apparatus which can transport large quantities of rod-shaped and/or other articles between one or more supplying machines and one or more consuming or processing (i.e., receiving) machines in such a way that a substantial supply of articles will normally dwell and/or advance between the supplying machine or machines and the receiving machine or machines to thus ensure that the receiving machine(s) can draw from the supply when the supplying machine(s) fails or fail to deliver articles at a desired rate or is or are idle, and that the supply can be increased by articles which are being delivered by the supplying machine(s) in the event of failure of the receiving machine(s).
Though the improved apparatus is particularly suitable for the transport of mass flows of rod-shaped articles of the tobacco processing industry, it can be utilized with equal or similar advantage for the transport of other articles which may but need not be rod-shaped and which may but need not form one or more mass flows. By way of example only, the improved apparatus can be utilized with advantage for the transport and temporary storage of catamenial tampons and/or other articles (e.g., in the form of packets, boxes or the like) which are or which can be turned out by modern mass producing machines.
A modern production line often comprises a number of different machines, apparatus, reservoirs and/or other components which serve for the making, transporting, storage and/or processing of commodities. For example, a production line which turns out filter cigarettes can contain a maker of plain cigarettes, a filter tipping machine which assembles plain cigarettes with filter rod sections to form filter cigarettes, a filter rod making machine which supplies filter rod sections to the filter tipping machine, a reservoir between the filter rod making and filter tipping machines, a reservoir between the cigarette maker and the filter tipping machine, a cigarette packing machine which receives filter cigarettes from the filter tipping machine, a reservoir between the tipping and packing machines, a cellophaning machine which is located downstream of the packing machine to provide each pack with a transparent outer envelope normally containing a so-called tear strip, a carton filling machine downstream of the cellophaning machine, and a carton boxing or baling machine downstream of the carton filling machine. The purpose of reservoirs is to avoid frequent stoppages of the entire production line, e.g., due to failure of the cigarette making machine to supply the tipping machine with a requisite quantity of plain cigarettes per unit of time or due to the failure of the filter rod making machine to supply the tipping machine with a requisite quantity of filter rod sections per unit of time. In other words, the purpose of the reservoirs is to compensate for occasional failure of adjacent machines and/or apparatus to deliver products to the next-following machines or to supply requisite quantities of such products. The reservoirs supply the products during idling of the preceding machine or machines as well as when the output of the preceding machine or machines is below normal. For example, a cigarette making machine can be temporarily out of commission as a result of tearing of cigarette paper or other wrapping material which is draped around a rod-like tobacco filler to form therewith a continuous tobacco rod which is to be subdivided into cigarettes of unit length or multiple unit length. A tipping machine is likely to be slowed down or idled in response to failure to receive so-called tipping paper which is draped about the end portions of plain cigarettes and about portions of or about entire filter rod sections to form filter cigarettes of unit length or multiple unit length.
German patent application Serial No. 33 45 117 A 1 of Mattei (Published Jun. 20, 1984) and the corresponding British patent application Serial No. 2 133 759 disclose a production line including a cigarette making machine and a cigarette packing machine. The two machines are connected to each other by a mass flow conveyor system which is capable of transporting a multi-layer stream of plain cigarettes extending transversely of the direction of advancement from the maker to the packing machine. The conveyor system includes two so-called first-in last-out reservoirs, namely a straight horizontal reservoir and an upright reservoir which is designed to store an elongated stream of cigarettes in the form of a helix having convolutions spacedly surrounding a vertical axis. A drawback of such reservoirs is that certain cigarettes are compelled to remain therein for practically infinite periods of time. The reason is that first-in last-out reservoirs are highly unlikely to be emptied in actual use of the production line, i.e., the quantities of cigarettes which are confined therein are likely to fluctuate but at least some cigarettes will normally remain in each reservoir. These remaining cigarettes were first to be introduced into the respective reservoirs and, in the absence of intentional complete evacuation of the reservoirs at certain intervals, are apt to remain in the respective reservoirs for very long periods of time. This can affect the quality (such as the moisture content) of the confined rod-shaped articles. The just enumerated drawbacks of first-in last-out reservoirs more than compensate for their advantage, such as their ability to confine large quantities of articles in a relatively small space. This holds particularly true for an upright reservoir if such reservoir is to be used in a plant wherein the reservoir can extend vertically but has little room to extend horizontally along the floor or even at a certain distance above the floor. It has been found that losses due to a lowering of the quality of cigarettes which remain confined in the respective first-in last-out reservoirs for extended periods of time and must be discarded in order to prevent them from reaching the packing machine (and hence the consumers) are rather high and constitute a deterrent to the use of such reservoirs in many production lines.
German patent application Serial No. 2 234 287 of Reinestad et al. (published Jan. 25, 1973) discloses belt conveyors having helically convoluted portions which can receive relatively large quantities of confined commodities. The inventors are concerned with the problem of ensuring adequate tensioning of the belt or belts for the purpose of reducing wear, slippage of conveyed commodities relative to the belt or belts and excessive energy requirements of the prime mover(s) serving to advance the belt or belts along one or more endless paths. A drawback of the conveyors which are disclosed in the application of Reinestad et al. is that they cannot accept varying quantities of commodities, i.e., the length of the path for the transport of commodities from a location where the conveyors receive such commodities to a location where the commodities leave the conveyors remains unchanged. The inventors propose to employ the belt conveyors as a means for advancing commodities (such as foodstuffs) past refrigerating, heating, sterilizing and/or other treating stations. However, the conveyors cannot be used to compensate for differences between the output or outputs of one or more supplying machines and the requirements of one or more receiving machines.
U.S. Pat. No. 4,339,025 granted Jul. 13, 1982 to McCombie discloses a conveyor for cigarettes or other rod-shaped articles which is used in a first-in last-out reservoir. The reservoir can store a larger or smaller quantity of articles; however, the articles which were first to enter the reservoir are last to leave the reservoir on their way toward the next-following machine. The drawbacks of such conveyors and reservoirs are the same as those discussed hereinabove in connection with the proposal of Mattei.